WASHINGTON (CNN) --Miguel Estrada, nominee for the U.S. Court of Appeals for the District of Columbia, withdrew his name from consideration Thursday after spending more than two years in limbo amid partisan wrangling over President Bush's judicial nominations.

Estrada, 42, a Honduran immigrant, would have been the first Hispanic to sit on that court, which sometimes serves as a steppingstone to the U.S. Supreme Court.

He was nominated by Bush in May 2001, but Senate Democrats used a filibuster to block his approval.

"I believe that the time has come to return my full attention to the practice of law and to regain the ability to make long-term plans for my family," Estrada said in a letter to Bush.

Estrada did not mention the opposition to his nomination. But Bush slammed Senate Democrats for what he described as their "disgraceful treatment" of Estrada, saying the nomination deserved an up-or-down vote.

"The treatment of this fine man is an unfortunate chapter in the Senate's history," Bush said in a written statement.

Calling the demise of Estrada's nomination a "dark moment," Senate Majority Leader Bill Frist, R-Tennessee, predicted Democrats will reap a backlash from the American public for using a filibuster to kill an appeals court nomination for the first time in history.

Frist also said "all options are open" for Republicans battling two other filibusters of Bush's judicial nominees, including using parliamentary maneuvers and changing Senate rules to make breaking a filibuster easier.

But unapologetic Senate Democrats claimed victory and vowed to continue trying to block any Bush nominees who are, in the words of Sen. Charles Schumer of New York, "far beyond the mainstream."

Estrada's nomination had enough support to pass the Senate, which requires only a simple majority.

But Republicans, despite repeated tries, could not muster the 60 votes needed to block the filibuster by Democrats.

The other two other Bush nominees Senate Democrats are filibustering are Texas Supreme Court Justice Priscilla Owen, nominated for the 5th U.S. Circuit Court of Appeals in New Orleans, and Alabama Attorney General Bill Pryor, nominated for the Atlanta-based 11th U.S. Circuit Court of Appeals.

The treatment of this fine man is an unfortunate chapter in the Senate's history.

-- President Bush

One of the handful of Senate Democrats to break ranks and oppose the filibusters, Zell Miller of Georgia, said Estrada "has become the latest victim of Washington's partisan, obstructionist politics."

"All of the president's nominees to the judiciary should have an up or down vote on the Senate floor. It's that simple. Anything otherwise is un-American and un-democratic," Miller said in a statement.

Estrada, a former clerk to Supreme Court Justice Anthony Kennedy and an assistant solicitor general during the Clinton administration, is a partner in a Washington law firm. He emigrated to the United States as a teenager.

Estrada's supporters charged that the Democrats were unfairly blocking a well-qualified candidate because of his conservative views and because they did not want to give Bush credit for nominating a Hispanic.

House Majority Leader Tom DeLay, R-Texas, accused Senate Democrats of "character assassination" and said their filibuster of the Estrada nomination amounted to a "political hate crime."

Kennedy praises 'victory'

But Sen. Edward Kennedy, D-Massachusetts, said the withdrawal was a "a victory for the Constitution."

"It reflects a clear recognition by Miguel Estrada, and, hopefully this White House, that under the Constitution the Senate has shared power over judicial appointments," Kennedy said.

Bush had called the Democrats' action a "disgrace" and vowed to fight until Estrada won approval.

Estrada's Democratic critics said he had not answered questions about several key court cases, including some involving abortion and affirmative action.

They also objected to a decision by the White House not to provide access to documents Estrada prepared when he was assistant solicitor general.

Under the Constitution, the Senate has shared power over judicial appointments.

-- Sen. Edward Kennedy

All seven living former solicitors general, including three who served under Democratic presidents, had opposed release of the internal work documents, calling them "highly privileged."

The dispute over Estrada is part of a larger and increasingly bitter struggle over Bush's judicial nominations in the Republican-controlled Senate.

Democrats are under pressure from interest groups in their party's base to hold the line against Bush's conservative nominees.

When they controlled the Senate earlier in Bush's term, Senate Democrats could block nominations in committee. But once Republicans took control after the 2002 elections, Democrats had to resort to the filibuster, a parliamentary maneuver, to thwart Bush's nominations.

Republicans charged that tactic was an abuse of the Senate's "advice and consent" constitutional power on judicial nominations by, in effect, changing the requirement for approval to 60 votes rather than a simple majority.